The haze was described by Maggie in a Summer Update, when Parson attempted to cross a hex boundary. She describes how crossing a border feels, saying that one simply "feels" their Move drop, and the hex gains new clarity.
Based on that, I'd assume seeing more than just the adjacent hex requires a tower or similar bonus, or perhaps it's just a matter of impaired detail, so the column was only visible because of the sheer number of units.
I think Jillian comments somewhere about how far ahead she can see the terrain, it was either sometime that she was flying, or while she was a Fugitive. It'll take a while for me to find where though. That's the reference we really need, since we care about terrain, not units.
"I'm afraid I don't understand. And also afraid that I do."
Two guys with basically the same name in a discussion about a character getting cloned.
There's gotta be a good joke in here somewhere.